Abstract The Campanian-Maastrichtian shallow-marine strata of the south-central Pyrenees
include eight calcarenite horizons, interstratified within thick siliciclastic deposits, that
contain characteristic rudist associations. From older to younger, they are listed below. 1-
Hippurites Iamart-ki horizon 2-Rudist-free horizon 3-Hippurites radiosus horizon 4-
Radiolitella pulchella horizon 5-Hippuritella castroi lowcr horizon 6-Hippuritella castroi
sensu stricto horizon 7—Biradiolizes moroi horizon 8-b'iraa'i0liles chaperi horizon The …